<?php
/**
 * Zend Framework
 * LICENSE
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 * @category Zend
 * @package Zend_Filter
 * @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
 * @license http://framework.zend.com/license/new-bsd New BSD License
 * @version $Id: Gz.php 24593 2012-01-05 20:35:02Z matthew $
 */
/**
 *
 * @see Zend_Filter_Compress_CompressAbstract
 */
require_once 'Zend/Filter/Compress/CompressAbstract.php';

/**
 * Compression adapter for Gzip (ZLib)
 * @category Zend
 * @package Zend_Filter
 * @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
 * @license http://framework.zend.com/license/new-bsd New BSD License
 */
class Zend_Filter_Compress_Gz extends Zend_Filter_Compress_CompressAbstract {

    /**
     * Compression Options
     * array(
     * 'level' => Compression level 0-9
     * 'mode' => Compression mode, can be 'compress', 'deflate'
     * 'archive' => Archive to use
     * )
     * @var array
     */
    protected $_options = array('level' => 9, 'mode' => 'compress', 'archive' => null);

    /**
     * Class constructor
     * @param array|Zend_Config|null $options (Optional) Options to set
     */
    public function __construct ($options = null) {
        if ( ! extension_loaded ('zlib')) {
            require_once 'Zend/Filter/Exception.php';
            throw new Zend_Filter_Exception ('This filter needs the zlib extension');
        }
        parent::__construct ($options);
    }

    /**
     * Returns the set compression level
     * @return integer
     */
    public function getLevel () {
        return $this -> _options['level'];
    }

    /**
     * Sets a new compression level
     * @param integer $level
     * @return Zend_Filter_Compress_Gz
     */
    public function setLevel ($level) {
        if (($level < 0) || ($level > 9)) {
            require_once 'Zend/Filter/Exception.php';
            throw new Zend_Filter_Exception ('Level must be between 0 and 9');
        }
        $this -> _options['level'] = (int) $level;
        return $this;
    }

    /**
     * Returns the set compression mode
     * @return string
     */
    public function getMode () {
        return $this -> _options['mode'];
    }

    /**
     * Sets a new compression mode
     * @param string $mode Supported are 'compress', 'deflate' and 'file'
     */
    public function setMode ($mode) {
        if (($mode != 'compress') && ($mode != 'deflate')) {
            require_once 'Zend/Filter/Exception.php';
            throw new Zend_Filter_Exception ('Given compression mode not supported');
        }
        $this -> _options['mode'] = $mode;
        return $this;
    }

    /**
     * Returns the set archive
     * @return string
     */
    public function getArchive () {
        return $this -> _options['archive'];
    }

    /**
     * Sets the archive to use for de-/compression
     * @param string $archive Archive to use
     * @return Zend_Filter_Compress_Gz
     */
    public function setArchive ($archive) {
        $this -> _options['archive'] = (string) $archive;
        return $this;
    }

    /**
     * Compresses the given content
     * @param string $content
     * @return string
     */
    public function compress ($content) {
        $archive = $this -> getArchive ();
        if ( ! empty ($archive)) {
            $file = gzopen ($archive, 'w' . $this -> getLevel ());
            if ( ! $file) {
                require_once 'Zend/Filter/Exception.php';
                throw new Zend_Filter_Exception ("Error opening the archive '" . $this -> _options['archive'] . "'");
            }
            gzwrite ($file, $content);
            gzclose ($file);
            $compressed = true;
        } else 
            if ($this -> _options['mode'] == 'deflate') {
                $compressed = gzdeflate ($content, $this -> getLevel ());
            } else {
                $compressed = gzcompress ($content, $this -> getLevel ());
            }
        if ( ! $compressed) {
            require_once 'Zend/Filter/Exception.php';
            throw new Zend_Filter_Exception ('Error during compression');
        }
        return $compressed;
    }

    /**
     * Decompresses the given content
     * @param string $content
     * @return string
     */
    public function decompress ($content) {
        $archive = $this -> getArchive ();
        $mode = $this -> getMode ();
        if (file_exists ($content)) {
            $archive = $content;
        }
        if (file_exists ($archive)) {
            $handler = fopen ($archive, "rb");
            if ( ! $handler) {
                require_once 'Zend/Filter/Exception.php';
                throw new Zend_Filter_Exception ("Error opening the archive '" . $archive . "'");
            }
            fseek ($handler,  - 4, SEEK_END);
            $packet = fread ($handler, 4);
            $bytes = unpack ("V", $packet);
            $size = end ($bytes);
            fclose ($handler);
            $file = gzopen ($archive, 'r');
            $compressed = gzread ($file, $size);
            gzclose ($file);
        } else 
            if ($mode == 'deflate') {
                $compressed = gzinflate ($content);
            } else {
                $compressed = gzuncompress ($content);
            }
        if ( ! $compressed) {
            require_once 'Zend/Filter/Exception.php';
            throw new Zend_Filter_Exception ('Error during compression');
        }
        return $compressed;
    }

    /**
     * Returns the adapter name
     * @return string
     */
    public function toString () {
        return 'Gz';
    }

}
